Isolation of rainbow trout neutrophils with an anti-granulocyte monoclonal antibody

A magnetic cell sorting system has been optimised for the purification of rainbow trout neutrophils using a monoclonal antibody (E3D9) raised against Atlantic salmon neutrophils. The purified neutrophils have good viability (85%) and purity (~92%), and were functional in respiratory burst and migration assays. The isolated neutrophils responded rapidly to PMA stimulation, producing levels of superoxide anion (4.85 nmols superoxide min−1/106 cells) approximately twice as high as macrophages from the same species. In the migration assay, there was a four-fold increase in migrating cells using the purified neutrophils compared with unfractionated blood leucocytes, and a relatively high neutrophil migratory activity was seen in the absence of serum.